When port availability changes, send a subscription event for the
owning card.
+## v26, implemented by >= 2.0
+
+In reply from PA_COMMAND_GET_CARD_INFO (and thus
+PA_COMMAND_GET_CARD_INFO_LIST), the following is added:
+
+ uint32_t n_ports
+
+...followed by n_ports extended port entries, which look like this:
+
+ string name
+ string description
+ uint32_t priority
+ uint32_t available
+ uint8_t direction
+ proplist
+ uint32_t n_profiles
+ string profile_name_1
+ ...
+ string profile_name_n
+
+Profile names must match earlier sent profile names for the same card.
+
+
#### If you just changed the protocol, read this
## module-tunnel depends on the sink/source/sink-input/source-input protocol
## internals, so if you changed these, you might have broken module-tunnel.